Automatic shutoff valve



Nov. 7, 1950 E. A. DUNN AUTOMATIG SHUTOFF VALVE Filed June 20, 1947 Patented Nov. 7, 19 50 OFFICE f2,52's,s22

AUTOMATIC SHUTOFF VALVE Ernest A. Dunn, Long Beach, Calif.

Application June 20, 1947, Serial No. 755,880

, direction by a spring, and the movement of the piston being retarded due to the flow of a fluid through a restricted port.

Another object of my invention is to provide a novel automatic shut off valve which is compact, simple in construction, and the parts of which are simple, and will therefore not'get out of order or cease to function. Other objects, advantages and features-of invention may appear from the accompanying drawing, the subjoined detailed description and the appended claims.

In the drawing the figure in the drawing is a longitudinal sectional view of my automatic shut off valve. f

Referring more particularly to the drawing, the numeral-I indicates a valve fitting, and this fitting includes the outlet port 2. A cage 3 is threaded on to the fitting I, or otherwise removably attached thereto, this cage includes the intake port 4. The fitting I includes an opening 5 in which a ball valve 6 is seated. A spring I is mounted in the cage 3 and bears against the ball 6, thus urging the-ball against its seat and tending to close the passage from the intake 4 to the outletZ. A cylinder 8 screws on to the fitting I, or is otherwise detachably secured to I the fitting. A shaft 9 extends through the cylinder 8 and into the fitting I. and is adapted to engage the ball 6 to unseat this ball, and permit the flow of fluid throughuthevalve. Packing III in the fitting I, and packing II in the cylinder 2 Claims. (01. 251 -138) is operating, the valve head I1 is closed.

The piston I2 may be provided with a guide ring I5 through which the shaft 9 extends, and this guide ring is provided with ports I6 through which fluid may pass. A valve head H on the shaft 9 fits either in the ring I5 as shown, or in the piston I2, if desired, and when the valve In operation, the shaft 9 is pushed inward manually, and the ball 6 is unseated against the tension ofthe spring I Fluid then flows from the intake port 4 thence through the passage 5 and out through the outlet port 2. As the shaft 9 is pushed inwardly, the valve head I1 is unseated and fluid in the chamber I8 flows past the valve head I1, and through the ports I6 to the chamber I9 on the outer side of the piston I2. The spring l3 will then press the piston I2 inwardly until the piston engages thevalve head I I, closing this valve and also preventing further movement of the piston. The ball 6 is opened as previously described, and the spring I is tending to close this ball, and also exerts pressure against the shaft 9, and tends to press the piston I2 'outwardly,'all of which-will be evident.

The outward movement of the piston I2 is permitted only by displacement of the fluid on the outer side of the piston, that is, this fluid must flow from one side of the piston to the other. This flow of fluid is permitted by the small port or orifice I4, and therefore, the piston will slowly move outwardly in the cylinder 8, the ball is gradually returned to its seated position,

5 and shuts offthe flow of fluid through the valve amount of inward movement of the shaft 9.

8 surrounds the shaft 9 and prevents leakage of *fiuid past this shaft. v

A piston I2 is mounted in the cylinder 8', and the piston is urged inwardlyby a relatively light spring I3. The spring I3 has less tension than the spring I and the purpose of this will be further described. A bleed port I4 extends through the piston I2 andthe purpose of this bleed port is to allow fluid to pass slowly through the piston and from one side thereof to the other, as the piston tends to move under spring pressure, all of which will be subsequently described.

Having described my invention, I claim: 1. A dash-pot mechanism for use with automatic shut-off valves comprising a body having valve therein, a valve actuating shaft extending into the body to actuate said valve therein, a cylinder on the body and surrounding the shaft,

a piston in said cylinder, said piston having a ing a bleed port therein, said piston being freely moveable longitudinally of the shaft, a valve head on the shaft, a, seat in the piston to receive UNITED STATES PATENTS Name Datev Bardsley Aug. 4, 1914 Peck Feb. 28, 1939 Coleman Feb 25, 1947 FOREIGN PATENTS Country Date Australia 1930 Australia 1941 

